Refrigeration system for vehicles



Dec. 25, 1934 B, 5 055 1,985,636

REFRIGERATION SYSTEM FOR VEHICLES Filed Dec. 19, 1935 5 Sheets-Sheet l L LJULJLJLJLLJ [J [U INVENTOR.

BENJAMIN 5. F055, I

jaw M 3W.

ATTORNEYS.

Dec. 25, 1934. B. s. FOSS REFRIGERATION SYSTEM FOR VEHICLES Filed 090. 19, 1933 3 Sheets-Sheet 2 JNVENTOR. BENJAMIN S. Foss, M flmw I ATTORNEYS.

Dec. 25 1934,

B; 5. F055 REFRIGERATION SYSTEM FOR VEHICLES 3 Sheets-Sheet 3 NEHED kmmSqIu ZoiwsQEo Filed Dec. -19, 1953 mN miou 10mm INVENTOR. BENJAMIN 5. Foss,

M a Quad/M A TTORNEYS.

Patented Dec. 25, 1934 PATENT orFicE anr'arosaarrou SYSTEM Foa vnrncms Benjamin S. Foss,

lirookline, Mala, assignor to B. F. SturtevantOompany, Boston, Mass.

I Application December 1 9, 1933, Serial No. 703,052

4 Claims. (01. 257

This invention relates to the conditioning of air for human comfort, and relates more particularly to the refrigeration and dehumidiflcation of air circulated through passenger vehicles in summer and the heating and humidificationof the air during winter.

It is now becoming well known that human comfort requires that the air within an enclosure should be not only circulated to provide sufficient ventilation, but should in winter, be warmed, with moisture added to maintain the proper relative humidity, and in summer should be cooled, and moisture extracted from it, to overcome the excessive humidity which .is usually present.

While the conditioning of air for motion picture theaters, hotel, ofllce and industrial buildings has been developed to a high degree in recent years, the air conditioningof vehicles, and particularly railway cars, has been more or less neglected, due, perhaps, to the peculiar problems involved and the many difficulties present. Among the difllculties which present themselves are the lack of space in a railway car which already of necessity has had to accommodate the maximum of equipment in the minimum of space, the excessive refrigeration equipment which would have to be carried. if the ordinary method of conditioning buildings were followed, the changing temperature conditions through which a railway car must pass, the cost of the equipment, and

, other difficulties. The weight of refrigerating systems is a serious factor, particularly when this weight must be carried all the year round.

At the present time there is much thought being devoted to the deevlopment of high speed and so-called stream-lined passenger vehicles. Railroads are experimenting with very light streamlined trains propelled by Diesel and other forms of internal combustion engines; The streamlined trains which have so far been designed and operated have been equipped with refrigeration plants for providing the cooling effect in the air conditioning systems installed, the refrigeration plants being operated electrically, through the prime mover, or have been driven through movement of the train. In all cases, additional power over that required to propel the train has been required for operating refrigeration equipment.

According to this invention, heat from the exhaust gases of an internal combustion engine, which drives a er vehicle, is utilized to rovide the necessary refrigeration required for air conditioning purposes. lhe exhaust gases from a high powered internal combustion engine,

55 onieavingthecombustionehamberI,haveatem-,

' densing action of the steam which is condensed perature of approximately 1000 F. This heat has been found sufllcient', according to this invention, to operate a refrigerant plant of adequate capacity to supply the necessary cooling effect for conditioning the air supplied to the passengers 5 within a vehicle.

In one embodiment of the invention, heat from the exhaust gases of an internal combustion engine, utilized to propel a passenger vehicle, generates steam in a steam boiler, which steam is used in a steam jet or injectortype refrigeration plant to produce a partial vacuum over a refrigerating fluid, such as water, through the injector action of, a steam jet, and also through the conafter passing through an injector. Water, which has its temperature lowered by this action, is circulated through a set of cooling coils in the upper portion of the vehicle and a fan forces recirculated and outside air over these 'coils and discharges it into the passenger space in the vehicle. In winter the steam is by-passed around the refrigeration plant and passes through heating coils over which the fan passes the air to be discharged into the passenger space. A steamhumidifler adds the necessary moisture to the discharged air.

In another embodiment of the invention, heat from the internal combustion engine is utilized in an absorption plant to produce the necessary 30 refrigeration action, the cooling coils of the air conditioning unit, mounted in the upper portion of the vehicle, acting as the evaporator of the refrigeration plant. For winter operation of the absorption and refrigeration plant is disc'ontinued, and heat from the exhaust'gases generates steam which, as in the other described embodiment, is passed through a heating coil and also adds the necessary humidity to the heated air.

'In another embodiment of the invention, the

'exhaust gases of the internal combustion engine pass through a steam boiler and generates steam which'is passed through a steam turbine connected to a refrigerant compressor.

A refrigerant from the refrigerant compressor passes through expansion coils in the air conditioning unit and the air to be cooled is passed by a fan over these coils. In the winter, the steam turbine is not operated, but steam is used, I as in the other described embodiments, to add heat and the necessary humidity to the air.

An object of the invention is to operate a refrigerant plant with the heat given of! by the exhaust gases from an internal combustion englue.

as v

Another object of. the invention is to generate steam by the heat from the exhaust gases of an internal combustion engine and to operate the refrigeration plant with the steam thus pro duced.

Another object of the invention is to operate.

an absorption refrigeration plant through the use of heat given off by the exhaust gases of an internal combustion engine.

Another object of the invention is to utilize the heat given off by the exhaust gases of an internal combustion engine to produce steam which operates a refrigerant compressor. I i

The invention will now be described with reference to the drawings, of which:

Fig. 1 is a side view of a so-called stream-lined railway car equipped with'an air conditioning system according to this invention;

Fig. 2 is a plan view looking downwardhr, with the top removed, of the passenger car of Fig. 1, and shows the circulation of the air conditioning system;

Fig. 3 is a view of the interior of the ear of Figs. 1 and 2, looking towards the end in which the air conditioning'unit is mounted, and shows the intake and discharge of the duetless air conditioning system;

Fig. 4 is a diagrammatic view of an absorption refrigeration plant connected to the exhaust pipe of an internal combustion engine, the exhaust gases producing the refrigerating effect;

Fig. 5 is a diagrammatic view of a steam jet refrigerating system'together with the steam,

plant, the exhaust gases from the internal combustion producing'steam, which, in turn, produces the refrigerating effect, and

Fig. 6 is a diagrammatic view showingapparatus for the production of steam by the heat in the exhaust gases of an internal combustion engine, this steam operating a steam turbine, which in turn drives a refrigerant compressor, which in turn provides a refrigerating effect for the refrigeration apparatus.

Referring-first to Figs. 1, 2 and 3, the arrangement of the heat exchange coils and the apparatus for circulating the air will be explained. The passenger car 10 is provided with the air conditioning unit 11 in one end and in the upper portion of the car. The unit 11 comprises the extended surface evaporator coils 12 and the extended surface heating coils 13. The blower 14,

driven by the electric motor 15, draws-outside air through the outside air inlet 16 and the recir culated air inlet 17, the indrawn air passing over the surfaces of the coils, through the blower 14, and being discharged through the discharge outlet 18.

The front portion of the car is provided with a grille 19 through which the outside air enters the car. Mounted in the front of the car, below the grille 19, are the two radiators 20, one on each side of the car, one of the radiators serving for the cooling water of the internal combustion engine and the other -radiator serving as a condenser for. the refrigerationapparatus. The rectangles 21 and 22, shown by the dotted lines of Fig. 1, indicate the space occupied by the refrigeration apparatus and the internal combustion engine respectively.

Referring now to Fig. 4, the operation of the absorption refrigeration system there shown will be explained. The exhaust gases from engine 23,

' which may be a' Diesel engine, or any other form tion refrigeration apparatus, and the other through the by-pass pipe 25. The pass of the exhaust gases through one or the other of these pipes is controlled by the combined manually and thermostatieally controlled valve 26 which permits exhaust gases to pass through the exhaust pipe 24 or the by-pass pipe 25, as the operation of the system requires. The lower portion of the tube 24 is provided, on the inside, with the extended surfaces 27 which serve to collect the heat given off by the exhaust gases, and to cause the lower portion of the pipe to become the hottest. Surrounding the exhaust pipe 24 is the sub-generator from the generator 30 through the rectifier 31,

where any water vapor entrained with the ammonia vapor is condensed. The water formed by condensation absorbs ammonia vapor, so that an ammonia solution of'strong concentration is returned to the generator through the pipe 32. The

ammonia remaining in the generator having been reduced in concentration, the weak liquid settles to the bottom of the generaton and, because of the diii'erenoe in level and also in pressure, is

forced through the heat exchanger 33 into the bottom of'the absorber 34.

The ammonia vapor leaves the rectifier 31 and passes through the condenser 35, where the coolving water, circulated in heat exchange relationship through the condenser, causes the vapor to llquefy. Inthe liquid state, the ammonia flows from the rectifier 31 through the pipe 86, which passes through the lower part of the gas heat exchanger 37 and discharges the liquid ammonia into the top of the evaporator coils 38.

Hydrogen gas enters the top of the evaporator coils 38 through the tube 39 and mixes with the ammonia vapor, causing, by Daltons law of partial pressures, a low temperature within the evaporator coils. The evaporator coils 39 of Fig. 4, according to this invention, are the extended surface coils 40 of Fig. 2, and, as has previously been explained, mixed recirculated and outside air is passed over these coils by blower action, is cooled, and forced into the passenger space of the car with wh'ch the apparatus is associated.

The mechanical mixture of hydrogen gas and ammonia vapor, after passing through the gas heat exchanger 37, enters the bottom of theabsorber 84, through the tube 41. A iiow of weak solution retums from the generatorthrough the heat exchanger 33 and contacts with the ammonia. and hydrogen gas mixture entering the absorber 34. The weak ammonia liquid passes over trays 42 in the absorber and absorbs ammonia vapor, causing the strength of the solution to increase. The stronger liquid, accumulates at the bottom of the absorber and is returned by gravity to the sub-generator 28. The hydrogen passes through the tube 43 from the absorber to the gas heat exchanger'3'7.

Cooling water for the condenser 35 and also for the cooling coils 44, which are placed around the absorber 34, is provided by a pump 45 from the radiator 46, which,.in this case, is one of the radiators 20 which have been described in connection with Fig. 1 as being mounted in the front of the car. The water in the radiator 46 is cooled by passage of the car through the air, and also cooled by the air being forced through it by the fan 47,

'whichmay be driven by an internal combustion engine or by an electric motor, which may be energized from a-storage battery and/or by an electric generator driven by the internalcombustion engine or connected to the car axles.

The thermostatically controlled valve 26 con trols the passage of the exhaust gases from the internal combustion engine 23 through the subgenerator 28 and the generator 30. The thermostat controls the valve to by-pass the exhaust gases through the by-pass pipe-25. at the end of the boiling point of the ammonia in the generstars. The pump 45 is connected by the mechanical connection 48 to a thermostatically controlled mechanism 49 which functions to maintain the cooling water going to the condenser 35 and to the coils 44 at the proper tempegature.

In cool weather, when it is not desirable or necessary to cool the air supplied to the passenger space in a car, the valve 26 may be adjusted to cause all of the exhaust gases to pass through the by-pass exhaust' pipe 25. The hot exhaust turn, cools the cylinder water circulated by the pump fed through'the pipe gases then pass through the steam generator 50, where a portion of the heat isutilized to generate steam in the steam coils.5l. The steam coils 51 are connected to the water system for cooling the internal combustion engine 23. The radiator 52, which corresponds to the other radiators 20 described inconnection with Fig. 1, operates in the usual manner to cool the water which, in water in the engine. The pump 53, which circulates the water through the radiator 52, is made, by, means of the valve 54 and the branch 55, to pass a small portion of the through the steam coils 51, where it is converted into steam, which then passes through the steam heating coils 57.. which correspond to the heating coils 38 of Fig. 2 and the humidifier -'7--a. Steam, after passing through the coils 5'7, enters the lower portion of the radiator 52, where it is condensed.

Obviously, the coils 51 maybe hot water coils and the heat of the cylinder walls, as well as that in the exhaust gases, may be used to heat hot water which is circulated through theheating coils 57. Thus, by regulation of the valve 54, a small amount of water-may be passed through the coils 51 and steam will be generated, or a large amount of water may be passed through they coils to act in a hot water heating system.

When the railway train is moving at low speed or standing in a station, the heat contained in the exhaust gases from the internal combustion engine driving the train is, of course, insufficient to supply the necessary refrigerating effect or heating effect for air conditioning Purp ses. There isprovided, therefore, according to this invention, an auxiliary source of hot gases'to supply the heat necessary for the operation of the cooling or heating system when the heat con-, tained in the exhaust gases is insufficient. This will now be described. The forced draft fuel burner 58, which may burn the fuel supplied to the engine 23 or may be supplied with any form of suitable fuel from thefuel tank 59, and which is provided with a blower 60, burns the atomized fuel in a combustion chamber 61 and the exhaust gases from the combustion chamber 61 are 62 and valve 63 to the exhaust manifold 64 of the engine 23. The blower 60 may be driven by an electric motor, and when the engine 23 is idle or idling, the motor for the blower 60 may be energized from a storage battery or any suitable auxiliary power source to operate the burner 58, and the valve 63 may be movement of the train,

' standing in a station,

opened to cause the heated exhaust gases to be supplied to the refrigeration apparatus or the heating coils 51 depending upon whether cooling or heating is required.-

In another embodiment of the invention, 11-

lustrated by Fig. 5, the heat in the exhaust gases of the internal combustion engine is caused to generate steam which is used in a steam jet or injector type refrigeration system. Exhaust gases from the engine 23, in this embodiment of the invention, pass from the exhaust manifold 64 through the valve 65, through the steam generator 66, or through the by-pass pipe '70, depend ing upon the setting of the valve. Contained within the steam generator 66 are the steam coils 6'7, over the surface of which the hot exhaust gases pass. A small amount of water is supplied continuously to steam coils6'7 by the pump 68, which circulates cooling water for the engine 23. The valve 69 may be adjusted to supply a small amount of water to the steam coils 6'7 or to shut off the supply of water to the steam coils altogether. Normally, valve 69 will be adjusted to permit the pump. 68 to force just suflicient water to the steam coils 67 to permit the evaporation-of sufficient water to supply the desired amount of steam through the supply pipe '71 to the steam injector '72.

In summer operation, the steam generated in the coils 6'7 will pass through the injector '72, the valve '73 being opened and the valve '74 being closed. The steam passing through the injector '72 creates a partial vacuum in the water tank '75 through injector action, and, after leaving the injector, passes through bottom of the radiator '77, where it is condensed. Both the condensing and the injector'action act in the usual manner to create a partial vacuum in the water tank '75, this causing a considerable reduction in the temperature of the water.

The cold water from the water. tank '75 is forced by means of the pump 78, which is preferably driven by an electric motor, which is, in turn,

battery, charged during through the cooling coils '79 in the air conditioning unit 80, which corresponds to the air conditioning unit 11 of Figs. 1, 2 and 3 of the drawings. The fan 81, driven by energized by a storage the electric motor 82, which is energized by a storage battery charged during movement of the train, forces air over the coils '79 and discharges it, of the car. The water leaving the coils 79, passes through the valve 83 and pipe 84 into the water tank '75, where it is again cooled.

In winter operation, steam from the coils 6'7, instead of passing through the steam jet refrigeration system, passes directly through the coils I9, which, in this case, serve to heat the air supplied to the passenger-space. The valves '73, 83, 96 and '86 are closed, the pump '78 is shut down, and the valves '74 and 85 are opened. This closes off the refrigeration system and permits steam to pass through the coils '79, the humidifier '79-0, and then through the pipe '76 to the radiator '77, where it is condensed. When the train is I thesame arrangement for providing heatedexhaust gases, as has-previously been described in connection with Fig.- 4, is utilized. The auxiliary heating system of Fig.

5 has been given the same numbers as the aux-.

the pipe '76 in the as shown'by Fig. 2, into the passenger space I running at low speed or In another embodiment of the invention, the heat in the "exhaust gases of the internal combustion engine is used to generate steam, which, in turn, rotates a steam turbine, which drives a refrigerant compressor. The refrigerant in the refriglsrant compressor is expanded in the cooling coils of the air conditioning system. embodiment of the invention is illustrated by Fig; 6... Since a great deal of apparatus required to""operate the refrigeration system of Fig. 6 is identical with that already illustrated by Fig. 5, the overlapping apparatus is not illustrated by Fig. 6, but instead an explanation is made as to how the refrigeration system of Fig. 6 may be used to replace that of Fig. 5. Steam from the boiler 66 passes to the steam turbine 87, which drivesthe refrigerant compressor 88. The refrigerant from the compressor 88 passes through the pipe 89 into the condenser 90, and then, through the pipe 91 and expansion valve 92, into the cooling coils 79, which now act as evaporator or expansion coils in a direct expansion refrigeration system.- The refrigerant leaves the coils 79 through the pipe 93 and circulates again through the compressor 88. I Cooling water for the condenser 90 is circulated by pump 94 from the radiator 95, which may be of the automobile type and which may be mounted as one of the radiators illustrated by Fig. 1, in the air stream passing the railway car, or, if desired, an electric motor may be provided to drive a fan which forces air over the cooling surfaces of the radiator.

In winter operation, the apparatus of Fig. 6 will not be used. Instead the steam will be used, as shown by Fig. 5,to heat and humidify the air supplied to the passenger space.

In the embodiments illustrated by Figs. 4, 5 and 6, the radiator for cooling the water of the internal combustion engine has been described and illustrated as acting as a condenser for condensing steam. Obviously, of course, separate radiators could be provided for condensing the steam and for supplying cooling water to the internal combustion engine. Whether or not a separate radiator should be used for condensing the steam depends upon the space available.and other factors entering into the question of design. Also, it depends upon whether a Diesel or gasoline engine is used for driving the train, and somewhat upon the weather conditions of the region in which it is expected that the train will operate. It is believed that one radiator may be used to serve both purposes if the amount of cooling surface provided is sufficient.

Whereas the present invention has been described in connection with a so-calledstreamlined railway train, it should be understood that the invention is not limited to this particular embodiment. but may be used in single railway cars, may be used in motor buses, or in any other form of passenger vehicle driven by one or more internal combustion engines, where it may be desired to make use of the energy contained in the exhaust gases for supplying the necessary cooling and heating effect for air conditioning purposes.

Whereas one or more embodiments of the in- This vention have been described for the purpose of illustration, it should be understood that the invention is not limited to the embodiments described since many modiflcations may be'made by those skilled in the art without departing from the spirit of the invention.

What is clamed is:

1. Apparatus for conditioning the air supplied to the passenger space within a passenger vehicle driven by an internal combustion engine, comprising an air cond.tioning unit communicating with the passenger space, means for supplying a heat exchange medium in contact with the air passing through said unit, a heat collecting surface forming a portion of said last mentioned means, means for passing the exhaust gases from said engine in contact with said surface to energize said last mentioned means, a combustion chamber, means for burning a fuel in said chamber for producing flue gases, and means for supplying said flue gases in contact with said surface to energize said last mentioned means as when said engine is inoperative or operating at below a critical speed.

2. Apparatus for cooling the air supplied to the passenger space within a passenger vehicle driven by an internal combustion engine, comprising an air cond tioning unit communicating with the passenger space, means for supplying a refrigerating fluid to said chamber, a heat collecting surface forming a portion of said last mentioned means, means for passing the exhaust gases from said engine in contact with'said surdriven by an internal combustion engine, comprising an air conditioning un t communicating with the passenger space, means for supplying a heating or a cooling medium to said unit, a heat collecting'surface forming a portion of said last mentioned means. means for passing the exhaust gases from. said eng ne in contact with said surface to energize said last mentioned means, a combustion chamber, means for burning a fuel in said chamber for producing flue gases, and means for supplying saidi'iue gases in contact with said surface to energize said last mentioned means as when said engine is inoperative or operating at below a critical speed.

4. Refrigeration apparatus comprising, in combination, an internal combustion engine, a combustion chamber, means for burning a fuel in said chamber to produce flue gases, means for 'produc ng a refrigerating effect, a heat collecting surface forming a part of said last mentioned means, and means for simultaneously passing the exhaust gases from said engine and flue gases from said chamber in contact with said surface to energize said last mentioned means.

BENJAMIN 8. F058. 

